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Total synthesis of ?-1C-galactosylceramide, an immunostimulatory C-glycosphingolipid, and confirmation of the stereochemistry in the first-generation synthesis.

ABSTRACT: A nonisosteric ?-C-glycoside analogue of KRN7000 (?-1C-GalCer, 1) was reported to induce a selective type of cytokine release in human invariant natural killer cells in vitro. We report here a very concise synthetic route to 1 and its analogue 1'. The key steps include olefin cross-metathesis, Sharpless asymmetric epoxidation, and epoxide opening by NaN(3)/NH(4)Cl. Inversion of configuration at the amide-bearing carbon in the phytosphingosine backbone constructed by epoxide opening in our previous synthesis of 1 was verified, indicating that remote group participation is not involved during the epoxide-opening reaction.

SUBMITTER: Liu Z

PROVIDER: S-EPMC3204185 | biostudies-literature | 2011 Nov

REPOSITORIES: biostudies-literature

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Total synthesis of α-1C-galactosylceramide, an immunostimulatory C-glycosphingolipid, and confirmation of the stereochemistry in the first-generation synthesis.

Liu Zheng Z Byun Hoe-Sup HS Bittman Robert R

The Journal of organic chemistry 20111004 21

A nonisosteric α-C-glycoside analogue of KRN7000 (α-1C-GalCer, 1) was reported to induce a selective type of cytokine release in human invariant natural killer cells in vitro. We report here a very concise synthetic route to 1 and its analogue 1'. The key steps include olefin cross-metathesis, Sharpless asymmetric epoxidation, and epoxide opening by NaN(3)/NH(4)Cl. Inversion of configuration at the amide-bearing carbon in the phytosphingosine backbone constructed by epoxide opening in our previo ...[more]

PMID: 21958232

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